Water-heater construction.



Ao' Y :SHEETS-SHEET 2.

Patented 0515,19, 1915.

F. L. 0.'WADSW0RT,H,` WATER HATER CONSTRUCTION. APPucmou many ofc. 26. |91 x,

l INVEN'I'OH` are the upper coils of the heater; D is a' j Figs. l and 2.

UN n

FRANK L. O. WADSWRTH, OF SEWICKLEY, PENNSYLVANIA.

WATER-HEATER CONSTRUCTION,

Specification of Iietters Patent.

Application filed December 26, 1911. Serial No. 667,947.

To all whom it may concern:

Be 1t known that I, FRANK L. O. VADS- ivoirrH, a citizen of the United States, resid-- illust-rated in the accompanying 'dra'ivings,^

wherein Figures l and 2 frontandV lside elevations respectively of the ordinary modern instantaneous heater, such as that shown 1n the patent to Shook, Number 993,723, with my improvement applied thereto; Fig. 3 is a transverse sect-ion on an. enlarged scale vthrough my controlling mechanism; and

Fig. 1 is a section through a modified form of the invention. y

Referring firstto the general arrangement of the heater parts as shown in Figs. l and 2, A is the casing of the heater; vB and C lower reverse coil connected to thev upper coilsv by means of the pipe E; Fare the burners mounted upon the usual b urner ring; G is the gas supply pipe; H is vthe casing of the gas valve for controlling the supply ofthe gas to the burners; Ils a pipe leading from the gas valve to the burner ring; and K is the casing of the water valve. 'llhe details and construction of the controlling mechanism which constitutes my invention will now be described, it being understood that such controlling mechanism is of general application and not limited to use` upon the particular type of heaters shown in Referring now to Fig. 3 in connections i with Figures 1 and 2; 1 is the coldwater pipe leading from the main, which pipe is y provided with a T 2, one side of which is connected with the chamber 3 in the casing K andthe other side of which is. connected tothe pipe el, such pipe connecting at its 5 upper end by means of the connection 4 (Fig.y 2) with the upper coil B of the heater.

The lower coil D of the heater has its-outlet end 5 connected to the lower end of the sr Ari'rr oFFioE.

Patented 0015.19, 1915.

thermostat casing AG, the pipe 6 (Fig. 2) l l leading fromv theupper end of s uch thermostatchainber G being the outlet leading tov the house service pipes. The chamber 3 and the thermostat chamber 6 are-connected`re spectively. by the passages'7 and 8 to the 0pposite ends of a cylinder 9 in which is located the fluid pressure actuated piston membei' 10. This member is connected by the stem 11,`passing through a stutting box 12,

to a link 13 pivoted on the end of the stem 1 i 14, of the gas valve 15. The piston member 10 is .preferably of the packing ring construction', and is held normally in position at the left hand end of the cylinder 9 by the unbalanced'pressure of the water in the cylinder against the head of the stem 11, this pressure beingsupplemented, if de sired,yby

a spring 16. Located in the thermostat chamber A6 is a double acting thermostatof the usual constructionfha-ving an A'outer positive member 17 and an inner negative member 18, the positive member 17 being secured in position. at the lower end of the thermostat chamber'and the inner negative member being secured -at its upper en d to they posiv tive member. 17, and bearing at its lower en'd on theV short arm of the thermostat lever.

19. The long arm ofv this latter lever enaolv gages with a "collar 20,mounte'd on a stem 21 which vpasses-through a stuffing box in the right' hand end of the cylinder 9. The stem 21 is threaded'to receive a'screw 22 which s crewextends clear through the stem 4 and constitutes an adjustable means for engaging the head of the stem 11. The collar v20is kept in engagement with thel thermostatlever by a strong compression spring 23.

lThegas valve 15 is of large diameter so that avery slight-longitudinal moveiiieutaway' from its seat Will open the gas valve portv to the full: capacity ofthe fuel supply and discharge pipes G and I.y Lalso avoid the necessity of using a packing box aroi'ind the stem of this valve by locating the head 15 so close jioo to the end of the valve box chamber that the withdrawal of said valve from its seat brings the Washer 26 into direct 'contact with the' headof the valve box chamber and thereby seals the opening around' the stem againstescape of any gas.' The head of the piston 1.0,.is similarly vprovided withl a Washer 26%i when the parts are inthe closed position'.

which seals the opening around the stem 11 The gas valve boX containingY the gas vvalve is also itted with anordinary plug valve 27, and a connection 28 leading to the ordinary-piles'l light which is provided for the ignition.. .of the gas supplied to the main burnersfthrough the pipe 1.'.

The 'operation of the above described apparatus i s""a's follows: lVhen no water is flowingthrough the heater and the temperature inthe thermostat chamber 6 is lower a than-that at which the thermostat may b'e set to act, the pressures at the inlet and outlet points, and in thechambers at the two ends of a cylinder 9 are the same,

water begins to flow through the heater, a difference i-n pressure will be set up at the inlet and outlet by reason of the resistance tothe passage of heater chamber or coils, and this difference of pressure. being communicated through the passages sides of the piston 10, the .latter will-1f the temperature of the out flving water is-less than that for which the thermostat'is set to act-be. moved to the right carrying with it i 4' ofwatervis stopped .the pressures -in the two ends of the cylinders 9 will again equalize themselves, and the' fluid actuated piston close.

lthe stem 11 and link 13fthereby opening the gas valve 15and .admitting fuel to the mainl burners of the heater. lfVhen the flow member 10 will return to its normal left hand position, allowing the fue valve 15 to' If while the water is still flowing the temperature in the thermostat chamber 6 rises above a certain point, .the expansion of the positive element 17 of the thermostat will allow the thermostat lever 19 to move sufficiently. to theleft to bringthe end of the screw 22 into contact with the head ofl the stem 11, and a further rise of temperature will allow the latter-to be forced'back to its normal left hand position by the pressure of the spring 23, the latter being of suficient strength to overcome the dierential pressure set up by the flow of the water on the opposing sides of the cylinder 9.-.

WVhen the temperature falls the contraction J.of the thermostat element 17 will move the thermostat lever 19 .to the right, thus compressing the spring 23 andwithdrawing the screw 22 from engagement with the head of the stem 11 and will allow the iuid pressure actuated piston member 10 to again open the gas valve l5.

In theconstruction shown in Fig. 4, 12 is (as before) a cold water supply pipe lead-l ing from the water main. This pipe enters a cored chambern2 which passes around one side of a diaphragm chamber 30, as indicated in the dotted lines and communicates with the interio'rof the latter through a port 72. At 4the upperv opening oI' the chamber and the. as valve 15 is held closed by the pressure. of the water on the stem`11. When the the liquid through the4 'Tand 8 tothe liquid on thetwo 32 there is placed a spring check valve 31 and from the opening above this check valve 'a pipe42 leads to the cold water inlet of the heater coils. This space is also in communication through a-port 32wi`th the right hand side of the diaphragm chamber 30. The fluidactuated pressure member consists in this case of a diaphragm 33 clamped at itsA outer edge between ltwo parts of the diap hragm chamber 30, and connected at its center with a stem 34 leading through a stuling box and coupled at its outer end to 'a U shaped link 35 which engages in turn with the lever 36. The short end of this lever 36 is pivoted on a stationary knife edge 37 on the head of the diaphragm chamber, and the long end is connected to the stem 142 ofthe gas valve 152 which is similar in` its construction to that shown in Fig. 1. The Astem 142 and the gas valve 152` are in this case held in their closed position by a -Spring 40, and this same spring serves also to'hold the lever 36in operative engagement with the parts 35 and 37. The stem 34 is made hollow `to receive an adjusting screw 41 which is threaded at its inner end through the central cap on the diaphragm 33. The water after passing through the heater chamber or coils emerges at the outlet 52, enters a'thermostat chamber 62 which is formed in the right hand end of the diaphragm chamber 30, and then enters the pipe 6? which connects with the house supply system. The thermostat chamber 62 is bored to receivethe liquid thermostat element 45, this thermostat element being constructed in the form of a corrugated box or cylinder with sides of thin vsheet metal and with ends of heavy plates one of which 46 forms a packed piston head separating the' right hand end of the diaphragm chamber 30 from the thermostat chamber 43, and the other of which constitutes a screw cap close ing the other end of said thermostat'chamber. The corrugated box 45 is filled with some liquid having a highthermal coeflicient of expansion, such as ether, or alcohol, or

crude petroleum, and is hermetically sealed.`

i The operation ofv this form of apparatus 1s the same as of that shown in Fig. 1, the only difference being `that whenv water is yflowing through the heater, the diierences the expansion of the liquid in. the thermo` stat box 45 will force the head 46 far enough to the left to either restore the diaphragm 33 to itsl initial position (thereby closing' 13 is suficientlto eontrolthe said movements and eie'ct'valclose temperature regulation of the gas va1ve, if it isfopen); or to prevent said dial'ohragm fromv leaving its "initial polsition until the l temperature falls again.

' Since the movement of the gas valve is many times greater thanv the movement ci. theA diaphragm 33 and stem 34, ayerysm'a-ll movement 'of the -headrt of the thermostat In theccn'struction'shown in llboth of' the j above 'guresf, the-actionvofithe .thermostat Y in closing the 'gas valve 1'5 i .nvo1ves' the 11eturn. of `the fluid actnatedfme'mber to its initial positionagainst the differential preslsure-[setup onthetwo sides -of that member bythe iiowoffthewater through thehe'ater. There is no diiculty however, inmaking la' v' ther'nlostat'. having suiiici'ent' power to do,

I j atedfmem'ber may be made quite small, and

saidmember lhas tofbe moved,4 not 'agalnst this', as the areaof the fiuidpressure actuv v-vthegluid'pressure. of thewater in the heater,

-I but'onlvfagainst the-differential pressureon illustrated its use, what I claim as ne-W; and

' l., In an automatic Water-heatereaburner',

ated' b'y the differential pressures in the `chambers for opening the 'gas valve, and a- .-thermostatic means governed by ythe heated Water and arranged so as'to move the said .member back toward the position at which the gasvalve isfclosed in 'case the tempera-v ture of -the Water inthe heater rises above' ya predetermined point,f theparts being arranged soithat a yielding closure of the gas valve is secured under. all conditions andso-v that lthe-thermostat means v.may continue inl 'its closing movement after .'the'rgas v alve is c dQSed.v A. y. .i

2. In an automatic Water heater, Va burner,

I.a gas valve'for controlling the; supply 'of gas to the burner, a vp'air'of pressure cham- -,bers' connected to portions of the 'heater havingdiifere'ntl Water pressure when the outlet fromfthe heater isi open, a member` actuated by the differential pressures in' the chambers -and arranged so as to pullthe gas valve open when the' direrential pressure is applied. to the member, and a thermostatio.

means. governed by the heated Water and ar-v ranged so as to force the said member back to' normal position and cause the closure of thega's valve when the temperature 'of the Water 'in' the heater-rises .above a predetermined point, there being a lost motion con-" nectlonbetvveen ythe thermostatic means and the gas valvewhereby 1 .the thermostatic 'l means may continue-its valve closing move#V 'ment' after "the gas valve s c losed,' Without imposing`l additional strain thereon.

.3. In an automatic-Water heater, a condui'tQthrough which th'evwater passes to be heated, a' vburn'en'zi, gas valve for lcontrolling the supply of gas to the'burner, Va pair of pressure chambers: lyingoutside the conduit but connected tio portions'of thecondut hav-- 4ing difere'nt Water'pressure when the outlet 'from the heater is open, means-actuated by thediferential pressures in. the chambers static means mounted 'independently-0f the said member-and arranged with a space between the parts of the said Water actuated means `and the thermostatic means when the outiet .from the heater 4is closed and the Water 4below a predetermined temperature butl governed by the .heated Water-and' arranged So as `to movethe 'saidl'vvater actuvatedjmeans back 'toward "the :position -at which the gas. valve .is closed; in case the `temperature of the .Water inthe'heater rises' l-abovega predetermined pointi" Y lIn testimony yvhereof 'I'V have-hereunto v for opening the gas valve, yand a vthermo- 

